The present invention relates to a flow meter for measuring the flow rate of a fluid such as a liquid fluid or a gaseous fluid, for example.
Known flow meters are subjected to any number of a plurality of disadvantages such as, for example, lack of accuracy except within a very narrow range of measured flow rates, high pressure losses, lack of linearity of the signal output, and unreliable indication of low flow rates, for example. In addition, most flow meters available on the market utilize a rotor provided with vanes or blades which are interposed in a light beam between a light source and a photosensitive device which measures the fluid flow rate as a function of the number of times the light beam is interrupted by the vanes or blades in a given time basis. Because the light beam travels a considerable distance within the fluid, it is subject to substantial absorption and dispersion while passed through liquid fluids lacking adequate light transmissivity.